1. Field of the Invention
The present invention is in the field of automated bale binding apparatuses engageable with bulk material compressors, in particular down presses.
2. Related Art
Baling of bulk material such as cotton is achieved by a compression apparatus, usually hydraulic, that compresses a volume of bulk material into a preconfigured bale shape and size. While still compressed, a bulk material bale binding apparatus engages the volume of compressed material at a baling station and binds it with wire strap. The strap can be metal or plastic.
The binding wire or strap is placed around a compressed volume of material in a baling station by feeding the wire or strap through a guide track that circumscribes the volume of material to be baled and guides the wire or strap into a loop around the bale. The loop is on a single plane, typically transverse to a long axis of the bale. Thereafter the wire or strap is released from the track, tightened around the material to be baled and fastened or knotted. These procedures are described in detail in prior art such as U.S. Pat. No. 6,637,324 to Stamps and U.S. Pat. No. 6,553,900 to Daniel, incorporated by reference herein.
It is in the nature of the compression apparatus that the circumscribing guide track must be disengageable at least in part, so that the compression machinery can eject a finished bale and compress a new bale. Prior art devices have achieved the disengagement of a portion of guide track either by swinging it upwards and away from the baling station, or sliding it outward from the baling station. These prior art solutions are typified by a fixed guide track portion and a moveable guide track portion. Both of they portions always remained within the plane of the bale loop, whether disengaged or not.
One form of bale compression apparatus is called a down press. Down presses are completely above a floor level and generally comprised of a first and second compression box for receiving a volume of bulk material to be baled. A first box is typically filled with loose material while a second box is simultaneously compressed and baled. Filling a box with loose material happens at a first position engaged with a tramper, which fills the box. Bale binding occurs at a second position having a vertically oriented hydraulic press for compressing the volume of bulk material. Binding occurs at the compression station. The boxes are transposed from the filler station to the compression and binding station by rotation around a central column. The boxes, press and central column are supported by a frame comprised of two end columns and a support lintel. Any automated bale binding apparatus used to bind the compressed volumes of bulk material must disengage to a position outside the circumference of the rotation of the two boxes around the center column. Disengagement of binding equipment in a direction perpendicular to a plane defined by the support frame would require moving the apparatus an impractical distance. Accordingly, prior art disengagement apparatuses that disengage guide track portions within the same plane as the bale loop are impractical for use with down presses, because the bale loop plane is perpendicular to the support frame.
Accordingly, there is a need in the art for automated bale binding equipment for use with down presses that disengages in a direction parallel with the frame of the down press and in a direction nonparallel to the bale loop plane. Concomitantly, there is a need for guide track components that are disengageable in a manner allowing such a lateral disengagement of the binding apparatus from the baling station. Additionally, there is a continuing need in the art for durability, compact size, and economy.
Further problems to address in automating binding of bales compressed by down presses include the following. Down presses commonly have a stand to be placed on the floor. On top of the stand is a bed which holds a lower platen and support structure for that platen. The support structure includes the slots into which lower guide track sections are inserted. The beds have preexisting dimensions of width and depth. These dimensions necessarily correspond to the dimensions of the compression boxes with which they interact. Accordingly, any lower guide track sections to be used for bale binders designed to be interoperative with down presses must be fit within the preexisting dimensions of the beds.
Another dimension to be accommodated is the space, sometimes known as a “stand off” space, between a wire knotter and the nearest edge of bale. If the stand off is too large, that is if the knotter is too far away from the bale, the resulting wire loops will be too large, and the bale will expand beyond the dimensions required to comply with the standards of the International Cotton Council for bale size. This stand off distance is on the order of seven inches.
Another design problem required to be met for automated baling with down packers is a minimum turning radius of guide track corner portions. This minimum radius is also in the order of seven inches. The most economical grade of wire to use that complies with the International Cotton Council standards for post binding strength and durability is 10 gauge wire. It is a property of 10 gauge wire that if a guide track guidance channel turns too sharply, that is, has a total turning radius of less than seven inches, the wire will frequently “jump” its track and jam. Therefore a shorter turning radius is impractical. There is a need in the art for an automatic bale binder for a down press that accommodates preexisting bed dimensions while still maintaining an adequate turning radius for 10 gauge wire.